66000639 has 16 divisors (see below), whose sum is σ = 92201472. Its totient is φ = 41915808.

The previous prime is 66000631. The next prime is 66000653. The reversal of 66000639 is 93600066.

It is not a de Polignac number, because 66000639 - 2³ = 66000631 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66000631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16329 + ... + 19965.

It is an arithmetic number, because the mean of its divisors is an integer number (5762592).

Almost surely, 2^66000639 is an apocalyptic number.

66000639 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

66000639 is a deficient number, since it is larger than the sum of its proper divisors (26200833).

66000639 is a wasteful number, since it uses less digits than its factorization.

66000639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3926.

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 66000639 is about 8124.0777322721. The cubic root of 66000639 is about 404.1253062764.

The spelling of 66000639 in words is "sixty-six million, six hundred thirty-nine", and thus it is an aban number.